Better late than never? Interannual and seasonal variability in the breeding chronology of gentoo penguins at Stranger Point, Antarctica

MARIANA A. JUARES; M. MERCEDES SANTOS; JAVIER NEGRETE; M. RITA SANTOS; JORGE A. MENNUCCI; EMILCE F. ROMBOLÁ; LUCRECIA LONGARZO; NÉSTOR R. CORIA; ALEJANDRO R. CARLINI

POLAR RESEARCH

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2013 vol. 32

0800-0395

Rapid climate change recorded in the western Antarctic Peninsula confronts species with less predictable conditions in the marine and terrestrial environ- ments. We analysed the breeding chronology and nesting site selection of gentoo penguins (Pygoscelis papua) at King George Island (Isla 25 de Mayo), Antarctica, during four seasons in which differences in snow presence and persistence on the ground were observed. We recorded an overall delay as well as seasonal asynchrony at the beginning of reproduction for those years with higher snow deposition. A redistribution of breeding groups was also observed. Nevertheless, the population breeding success and chicks? weight at fledging remained relatively constant, despite the delay in breeding chronology, the increased duration of foraging trips during the guard stage and the decreased weight of stomach contents during the crèche stage. We suggest that the plasticity of their trophic biology, along with the flexibility of their breeding phenology and relocation of breeding groups, may be complementary reasons why gentoo penguin populations in the region have remained stable in spite ofthe changing conditions currently registered.